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Four wells monitor the Wadge Coal seam and overburden, and two of the wells <br />are in hydraulic communication with the Wadge Impoundment (located in the <br />original mine area). Three wells remain in what is referred to as the Wadge <br />Lennox interburden. These wells exhibit normal seasonal variations. <br />Aquifer tests performed in the Wadge Coal seam indicate that the Wadge aquifer <br />exhibits a semi-confined condition with a transmissivity value of 377.1 gallons per <br />day per foot (gpd/ft). Wadge water levels, dependent upon well proximity to the <br />recharge area, show some seasonal variation. <br />Alluvium <br />There are three alluvial aquifer systems within the original Seneca II permit area: <br />the Grassy Creek alluvial aquifer, the Cow Camp Creek alluvial aquifer system <br />(drainage from below 004 pond to Fish Creek), and the Bond Creek alluvial <br />aquifer (drainage from below 008 pond to Fish Creek). The Fish Creek alluvial <br />aquifer is not within the Seneca II permit area, but may be affected by water <br />discharging from the permit area. The reduced permit area will include the Bond <br />Creek alluvial aquifer and may affect the Fish Creek alluvial aquifer. <br />Originally, nine wells were used to monitor alluvial water quality in the drainages. <br />Two wells are located along Cow Camp Creek, one along Bond Creek, two along <br />Grassy Creek and four along Little Grassy Creek. All of these wells exhibit <br />seasonal variations. With the reduced permit area, monitoring of the alluvium <br />will be reduced to one well (GW-S68-A) in the Bond Creek alluvium, and one <br />(008-AU-3) in the Fish Creek alluvium. <br />Spoils <br />The resaturation of portions of the backfilled pits has been expressed as spoil <br />aquifers. Water percolates through the replaced spoil material and flows <br />down-gradient until it reaches the lower-most highwall where the infiltration rate <br />into bedrock is much lower than flow through the spoil. When the elevation head <br />of the spoil aquifer exceeds the ground surface elevation, the spoil water <br />discharges in the form of springs at the topographically lowest point along the <br />reclaimed highwall. Nine spoil springs have been identified in the original permit <br />area, eight of which are monitored by Seneca Coal Company. In addition, Seneca <br />Coal Company has historically monitored thirteen spoil wells as part of the <br />approved monitoring plan. The reduced permit area will include one spoil spring <br />that will be monitored (Spoil Spring #9). <br />Water from the spoils exhibit elevated concentrations of sulfate, manganese, and <br />magnesium. TDS concentrations in water from spoil wells throughout the original <br />permit area have generally risen during the period of monitoring but seem to level <br />out at about 4000 mg/1. Several exceptions are S25-S, which has reached <br />14